Sidewalk
contractor stamps
This site is dedicated to the documentation, cataloging, and publication
of those symbols of labor known as contractor stamps. Most were placed
from the early 1900s through the late 1970s, but few contractors now use
them because of fear of litigation and a changing attitude toward craftwork.
Despite being cast in a durable medium, these marks are disappearing from
the urban landscape at a remarkable rate as curb cuts, buried utilities
repair, and general gentrification take their toll.

Much
can be learned from these artifacts, including construction dates and
patterns of urban development. But perhaps most importantly, these are
symbolic of the pride that tradesmen and women displayed in building our
country.

This is a work in progress. Current printer-friendly catalog may be downloaded here. For more information on the documentation and cataloging process of these images as well as community efforts to preserve them see attached page. Also feel free to look at a related article on the invisibility of union labels in bibliographic cataloging.
An excellent effort by Andrew Alden to document Oakland stamps can be seen here.
Thanks to Ken Duffy and Robert Rush for support and feedback.